6.1 Fats and Oils Introduction
Before You Come to Lab
Name: _________________________________
Watch the “How to Deep Fry” steps and video posted on Canvas.
- List the safety precautions for each component when frying.
Watch the “How Batters Work” video on Canvas.
- What are the two functions of water in a batter?
Watch the “What Are Emulsions?” video on Canvas.
- List 3–4 everyday food emulsions.
Watch the “Learn to Cook: Making an Emulsion” video on Canvas.
- When making mayonnaise, what speed should the oil be added to the egg yolk and lemon juice mixture?
Fats and Oils
Many foods we eat contain fats or oils, so it is important to understand the types and uses of fats and oils in food.
- Purpose: Fats and oils contribute to the flavor, mouthfeel, texture, and overall palatability of food.
- Examples: soybean oil, canola oil, peanut oil, corn oil, olive oil, shortening, butter, margarine, and lard
Terms
- Lipids: Umbrella term for fats and oils
- Oils: Liquid at room temperature
- Fats: Solid at room temperature
Lipids are made up of a triglyceride backbone and three fatty acids. The types of fatty acids dictate whether the lipid is a fat or oil at room temperature.
Draw a triglyceride here:
- Saturated or Unsaturated: the more unsaturated (more double bonds) the fatty acid has, the more likely it will be liquid at room temperature
- Chain Length (# of carbons): the longer the chain, the more likely to be a fat at room temperature
Deep Fat Frying
Deep Fat Frying is one way we use oil. It is just as the name implies – food is immersed in hot oil so it cooks quickly.
- Oil is an efficient cooking medium because the oil will reach higher temperatures than water — optimum around 375°F for frying, while water maxes out at the boiling point at 212°F.
- Deep-fat-fried food is crisp and/or crunchy on the outside and has a distinct fried flavor.
- Many fried foods are coated with a batter or breading before being fried.
- A batter is more liquid in nature, a breading is dry — both are used to coat a food that cannot be fried alone.
- High-starch foods (fries) can be fried without a batter or breading.
- Soybean, corn, and peanut oil work well for frying because they have a high smoke point.
- Frying oil deteriorates over time. Oil becomes darker, thicker, and off-flavors develop. Food absorbs more oil as the oil gets older.
Frying Safety
- Leave oil on the back burner
- Monitor the oil temperature and heating duration
- Be careful when placing food in and removing food from the fryer
- Use slotted spoons and white paper towels
- Drain excess oil from food when removing
- Have a baking sheet out to extinguish a fire
Emulsions
Fats and oils are often part of a food or drink containing water. Oil and water do not mix, so emulsions often need to be formed. To start it helps to think about the three dispersion types formed in water.
- Suspension: Large particles will separate out in a few minutes. Examples: orange juice with pulp and cream rising in milk.
- Colloid: Medium-sized particles, translucent/cloudy, emulsions, etc. Examples: salad dressings, protein in milk.
- Solution: Small particles completely dissolved and/or associated with the water molecules. Examples: salt water, sugar water, lactose in milk.
An emulsifier is an ingredient with a polar and non-polar end that allows oil and water to mix. Examples include egg yolk (lecithin), whole egg, paprika, and dry mustard.
An emulsion is a type of a colloid or colloidal dispersion of one liquid in another, in which liquids are immiscible with each other.
- Temporary: large droplets of oil, separates out quickly, ex. True French Dressing
- Semi-Permanent: medium-sized droplets of oil with a thickening agent, ex. Modified French Dressing and Fruit Salad Dressing
- Permanent: small-size droplets of oil with a strong emulsifier, ex. Mayonnaise and Cooked Salad Dressing
- Oil in Water Emulsion: oil droplets are suspended in the water phase, ex. salad dressing, milk
- Water in Oil Emulsion: water droplets are suspended in the oil phase, ex. butter and margarine
